Seeds such as peas, lentils, and beans have long been harvested for selling to the general public at a market place. In order to sell this produce however it is required that the produce have some consumer appeal. Consumers will tend to purchase more appealing produce and therefore it is necessary for producers to address the issue of appearance of the produce before the produce is brought to the market place.
When produce such as peas and beans are dehulled and split, the end product is dull. It is desired to take this dull product and make it shiny in appearance without contaminating it in any way. A significant problem occurs however when liquid is added to the products because of the high starch content. The liquid and starch form an adhesive mixture which causes lumps to form in the product. This can cause molding. Also to produce a proper shine additives must be supplied in some form or another to properly coat the product.
The known prior art in devices for blending or mixing additives do not supply enough liquid and do not distribute the additives evenly enough for produce with high starch such as peas and beans. These devices are not designed to mix large volumes of produce with additives and coat the produce in a continuous single stage machine while polishing the produce. They are most often in the form of batch processes which cannot keep up with the large volumes required by some producers.
The closest known prior art U.S. Pat. No. 4,465,017 to Simmons describes a seed coating machine having an upper and lower mixing drum. Liquid additives coat the seed in the upper mixing drum. The seeds are then passed from the upper drum to the lower drum through a drying chamber. In the lower drum powders are sifted onto the seed for adhering to the liquid additive previously applied. The machine requires time for drying and sifting operations making the machine unsuitable for large coating operations. Also the machine lacks the versatility to perform mixing or polishing operations as well as coating.
According to the invention there is provided an apparatus for mixing particulate material which includes a generally elongate housing having an input feed on an input end of the housing and an output discharge on an output and of the housing for flow of the particulate material through the housing. A shaft mounted within the housing for rotation about a longitudinal axis of the shaft is driven by a motor and carries at least one section of ribbon flighting mounted on the shaft for rotation with the shaft and arranged such that rotation of the shaft in a normal direction causes flow of the particulate material forwardly of the housing from the input end to the output end of the housing. A plurality of flow bars extend from the shaft at spaced positions along the length of the shaft and mounted on the shaft to rotate with the shaft and a plurality of retarder bars also extend from the shaft at spaced positions along the length of the shaft and mounted on the shaft to rotate with the shaft. Each of the flow bars and the retarder bars comprises a U-shaped member having two legs connected at an inner end to the shaft and an outer main cross-member connecting the legs at a position spaced outwardly from the shaft. Each of the flow bars is inclined to the axis of the shaft in a direction such that rotation of the shaft in the normal direction causes the flow bars to urge the particulate material forwardly of the housing and each of the retarder bars is inclined to the axis of the shaft in a direction such that rotation of the shaft in the normal direction causes the retarder bars to urge the particulate material rearwardly of the housing such that the flow bars and the retarder bars co-operate to effect mixing of the particulate material.
The apparatus can be used with a dispenser of dry and/or liquid additive materials for blending and polishing the particulate material.